Tamirabharani Waterbird Count spots over 21,000 birds of 69 species

The recently conducted Tamirabharani Waterbird Count in 68 irrigation tanks in Tirunelveli, Tenkasi, and Thoothukudi districts with the help of 250 volunteers has led to the spotting of over 21,000 waterbirds of 69 species.

The perennial Tamirabharani river and its tributaries, which collectively form the lifeline of the southern districts of Tamil Nadu by invigorating agriculture, are also home to several species of waterbirds, both domestic and migratory. The centuries-old irrigation system associated with the Tamirabharani river continuously supplies water for irrigation through a network of canals and irrigation tanks, earning the region the title of the ‘Rice bowl of southern Tamil Nadu’.

The tanks across these districts function as vital habitats for wetland birds and collectively support nearly 100 bird species, of which more than 30 are migratory and arrive from different parts of the world.

Waterbirds spotted at the Vellur Kaspa tank during the recently conducted Tamirabharani Waterbird Count
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Special Arrangement

With the objective of promoting conservation of waterbirds and their habitats, the Tamirabharani Waterbird Count (TWC) has been conducted annually since 2011 by the ATREE’s Agasthyamalai Community Conservation Centre (ACCC) with active participation from local voluntary organisations and the general public.

This year, the exercise was jointly organised by the Agasthyamalai Community Conservation Centre, Manimutharu, District Science Centre, Tirunelveli, Nellai Nature Club, Tirunelveli, Pearlcity Nature Society, Thoothukudi, and the Tamil Nadu Science Forum, Tenkasi. The survey was conducted from January 23 to 25 across 68 irrigation tanks in Tirunelveli, Tenkasi, and Thoothukudi. Over 250 volunteers, divided into eight teams, participated in the survey with guidance from bird experts.

Survey findings

A total of 21,091 wetland birds belonging to 69 species were recorded from the 68 irrigation tanks. The highest bird abundance was observed at Kadambakulam in Thoothukudi district with 2,292 birds of 45 species, followed by Vellur Kaspa (1,804 birds, 39 species), Perungulam (1,531 birds, 39 species), Gangaikondan tank in Tirunelveli district (1,232 birds, 32 species), and Melputhukudi Spring (1,217 birds, 35 species).

Among individual species, Little Cormorant recorded the highest numbers with 2,579 individuals, followed by Eurasian Coot (2,155), the migratory Whiskered Tern (1,148), Glossy Ibis (1,107), Pheasant-tailed Jacana (1,095), and the migratory Barn Swallow (1,093).

“More than 36% of the recorded birds were migratory species, using the Central Asian Flyway, which connects breeding grounds in northern Eurasia with wintering wetlands in South Asia, including India. The Tamirabharani irrigation tanks act as crucial habitats for these migratory birds. A total of 8,912 migratory birds were recorded, including the near threatened Black-tailed Godwit, and migratory duck species such as Bar-headed Goose, Northern Pintail, Garganey, and Eurasian Wigeon,” said M. Mathivanan, coordinator, TWC.

Active breeding was observed in several irrigation tanks, including the tanks in Vadakku Kazhuvur, Gangaikondan, Manur, and Maranthai in Tirunelveli district and Vagaikulam in Tenkasi district. Species such as Spot-billed Pelican, Black-headed Ibis, Glossy Ibis, Oriental Darter, Indian Shag, Little Cormorant, and Asian Openbill were observed breeding.

Thoothukudi district, housing sprawling larger irrigation tanks, supported higher bird abundance and species richness. In the 2026 TWC, Thoothukudi district accounted for 51% of total bird abundance and 80% of species diversity, underlining the importance of large irrigation tanks for both resident and migratory waterbirds.

‘Threats persist’

“Several threats continue to affect these critical habitats, including solid waste dumping, liquor consumption along tank bunds and bathing ghats, invasive plant and fish species, and sewage intrusion in urban tanks. These issues pose serious risks to waterbird habitats and require urgent management interventions,” Mr. Mathivanan said.

The irrigation tanks serve as wintering grounds, where migratory birds spend several months feeding and resting, and also as stopover sites that allow birds to replenish energy during long migratory journeys. The loss or degradation of these wetlands would disrupt international migratory routes. Therefore, the protection, restoration, and sustainable management of irrigation tanks are essential for the long-term conservation of waterbirds, he observed.

Published – February 11, 2026 12:18 pm IST